Remember to check out Parts 1 & 2 of our Cursed Child: The Journey extract series, looking at the themes of magic and music.

For the effect that signifies the use of the Time-Turner by Albus and Scorpius, [John] Tiffany knew he needed a big gesture.

“My first idea, which I played with a lot, was a kind of Wizard of Oz moment,” he explains. “That when we went back, we would either go black and white, but you can’t do black and white onstage actually, or go the opposite, so it would be a sepia world.” The difficulty and look of each made Tiffany think again.

“So, then I explored the Dark Arts,” he says with a laugh. As the characters place their hands around the Time- Turner, clock hands across the proscenium whirl around clock faces, the sound of ticking increases, garbled dialogue floats in and out, and then, suddenly . . . “There are people who love the fact that they don’t know how it’s done,” says Beestone. “Sometimes, when I’ve stood at the back, people will tell me their ideas about what it is and they’re totally wrong, which is very enjoyable.”

Producer Colin Callender came up with the best explanation of the Time-Turner effect, also called the wobble, for his young daughters. “I told them that there are stagehands outside the theater on both sides, and how it happens is that they shake the theater.” The effect of the Time-Turner takes a huge amount of skill from the performers. “They need to really understand the technical side of things,” says Harrison, “the technique of how they’re doing it, and why it won’t work if they deviate.” Body placement and positioning is critical to the illusion.

“But it should look natural and look simple,” says Fisher, “and if it does, that means they’re doing their job really well.” Add to that expressing the emotion of the character while doing it. “It takes a while for those things to bed down,” says Harrison, “which is why we rehearse it from the very, very, very beginning so that they can embody it and it becomes so second nature that the character is allowed to flow. Otherwise it halts actors from being able to deliver the character because suddenly they have to snap out and think, ‘Oh, I’ve got to stand here and do this and do that.’”

Harry Potter and the Cursed Child: The Journey, by Jody Revenson, publishes today in the UK and 5 November, 2019 in the US.

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